Lasers and Breathalyzer Reveal How Much Methane Cows Produce

Compared to a planet-obliterating meteor, massive cyber attack, devastating weather machine, or whatever other disaster movie scenarios Hollywood scriptwriters can come up with, a methane-filled cow fart or belch sounds kind of mild. But when it comes to real-life potential disaster scenarios, the amount of climate change-causing methane that’s pumped into our atmosphere turns out to be a pretty darn big problem. Methane is a far more damaging greenhouse gas than CO2 — by a massive 25 times.

To solve a problem, however, it’s important to first understand the scale of it. With that in mind, scientists from the United States Department of Agriculture (USDA) recently took a high-tech approach to measure bovine flatulence. As part of their research, they used devices including lasers, GPS trackers, and GreenFeed, a so-called “breathalyzer for cows.” Their purpose was to work out just how much methane is dispatched into the environment from cows in as accurate a way as possible.

The study involved analyzing Oklahoma cows with these tools. The cow breathalyzer worked by training cows to put their head into an open hood, containing food. While they were eating, the GreenFeed device then took samplings of their breath, making it possible to calculate accurate methane emissions. Meanwhile, the open-path lasers and GPS trackers were, respectively, used to detect trace gases in the air and to monitor the location of the herd. The experiment took place on a tallgrass prairie in central Oklahoma. It was repeated in three separate grazing periods — summer, fall, and winter — so that researchers could get a sense of how emissions vary over the course of a year, depending on forage quality.

They concluded that the average Oklahoma cow pumps out around 182 pounds of methane gas each year. While that might not sound all that much, the fact that there are close to 100 million domestic cattle in the United States of America means that, on a population basis, those belches and farts present a pretty sizeable problem.

One thing the researchers in this work didn’t do was to try and establish how to solve the issue. While that will hopefully change in the future, there are other scientists and engineers currently looking for ways to reduce the methane problem, such as by lessening our reliance on breeding cows for food by using other technologies such as lab-grown meat.